I had a birthday party at the TST branch 2 years ago. Frankly, if you are amazed by the regular classes, don't put too much hope in the birthday parties!
The Bday party staff are part-time! The english was not native like the instructor, which made us mad enough cuz my hubby found that they do not understand him very well! Then the same problem with the cake and food! Takes forever to get the children to eat and they basicly tell you that you should pay the extra to extend the party duration (when we booked the party) because it's rush with the standard length. Then why don't you just set a longer party time?!
The environment was good and the children enjoyed playing there, but apart from that, not much I liked! But then my friends said as long as my son was happy, I shouldn't complain!